Conradson carbon ("Concarbon") number or content is a measure of the characteristic tendency or propensity of a petroleum feedstream to form coke during processing. Feedstreams having a lower Concarbon number are more economically desirable as refinery feeds than feedstreams having a higher concarbon number. For example U.S. Pat. No. 5,514,252 discloses reductive electrochemical treatment of refinery streams which occurs at specified cathodic potentials. It is, therefore, desirable to develop processes for reducing the Concarbon number of feedstreams. Applicants have developed such a process.